Rappetty tap
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Rappetty tap
Makes the noise when revving up or down, but not idling. I checked the rockers and pushrods, they seem to be ok. I think i might have lost a lifter :(. It's a small metallic hammering noise.
Stupid self-aligning no-poly LT4 rockers. Can't wait to get some Pro Magnums. :yesnod:
[Modified by Glock'94, 5:36 PM 7/19/2002]
[Modified by Glock'94, 5:37 PM 7/19/2002]
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: (scorp508)
it's a little hot to even touch the cover. I'll wait until it cools down a little bit. I don't know how those plastic covers don't melt! :crazy:
[Modified by Glock'94, 5:34 PM 7/19/2002]
[Modified by Glock'94, 5:34 PM 7/19/2002]
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: (Glock'94)
Now I think it's a false alarm, that or losening the rockers down from about 30ft/lb to 18ft/lb made the noise go away. None of the lifters look bad. All are in good condition. I got it all put back together and it just sounds like the rockers are really really loud. Before I thought i could pin point a single sound, but now it sounds like all of the rockers .. so.
I think my next purchase for my vette will be some Pro Magnum rockers :yesnod: .
[Modified by Glock'94, 9:21 PM 7/19/2002]
I think my next purchase for my vette will be some Pro Magnum rockers :yesnod: .
[Modified by Glock'94, 9:21 PM 7/19/2002]
Pro
Joined: Mar 2001
Posts: 602
Likes: 1
From: Hacienda Heights, Ca. USA
Re: (Glock'94)
Be careful. If you can't trace the noise to the valvetrain it could be a loose rod bearing or a wrist pin. It could even be piston slap. I've heard the noise that you're describing before and I did the same valvetrain checks that you're doing. The noise got worse and louder as time went on until a rod let go and pretty much exploded the motor. Check it out real good! :eek:
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: (john25)
WOW. I am with the last guy. Something is making the noise. Noises like that usually are not good in an engine.
I don't mean to be negative just make sure you check everything. Could it be your cam bearings? And the noise is transfering up through your valve train?
Sorry guy! Hope you find its nothing. :confused:
This may be a stupid thing to mention, but it isn't exhaust leak is it?
[Modified by ski_dwn_it, 6:00 AM 7/20/2002]
I don't mean to be negative just make sure you check everything. Could it be your cam bearings? And the noise is transfering up through your valve train?
Sorry guy! Hope you find its nothing. :confused:
This may be a stupid thing to mention, but it isn't exhaust leak is it?
[Modified by ski_dwn_it, 6:00 AM 7/20/2002]
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: (john25)
It could even be piston slap.
R94LT1 had bearings that were gone, and I know what that sounds like.
It's neither of those. I've never heard a wrist pin going bad though. Also, to note, I'm pretty sure it's not at piston speed. I can watch the rockers and it looks like the sounds goes with them.
R94LT1 is stopping by the house in a few minutes to hear it so you can have input from another set of ears.
[Modified by Glock'94, 11:03 AM 7/20/2002]
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Le Mans Master
Joined: Apr 2001
Posts: 7,410
Likes: 252
From: Little Elm TX
Re: (Glock'94)
Since Glock'94's on vacation, I'll post what we found.
He had loosened the LT-4 rockers from about 40/lbs to the 18/lbs they where suppose to be. We both listened to it from start up to normal temps and it appears (for now) that the noise is gone. I personally noticed that the lifters were sounding "better" IMHO. They use to tick and now they have a machinery kind of hum to them. I'm wondering if the roller tips weren't binding before as tight as they were.
As for mine, he is correct on the bearings. Mine sounded a lot like a diesel truck engine :cry when the bearing went. I don't understand how anyone can own a motor that sounds like it's broke all the time. :rolleyes:
I can't wait till "R"'s is done and I can start :seeya again!
He had loosened the LT-4 rockers from about 40/lbs to the 18/lbs they where suppose to be. We both listened to it from start up to normal temps and it appears (for now) that the noise is gone. I personally noticed that the lifters were sounding "better" IMHO. They use to tick and now they have a machinery kind of hum to them. I'm wondering if the roller tips weren't binding before as tight as they were.
As for mine, he is correct on the bearings. Mine sounded a lot like a diesel truck engine :cry when the bearing went. I don't understand how anyone can own a motor that sounds like it's broke all the time. :rolleyes:
I can't wait till "R"'s is done and I can start :seeya again!